Topic: Cam Confusion and Problems

[Lammers000]

Hey guys,

So I bought my bike knowing that it had an oil circulation problem. Upon tearing it down completely (split case and all), I found that an oil gallery in the head at cylinder 4 was clogged, inhibiting oil circulation to cylinder 4's cam bearing. As a result, the damn thing eat itself to pieces, removing material from the cam itself. The cam tower was destroyed as well. However it doesnt seem that any metal flakes or chips did any damage else where in the head / valve cover cavity.

My concern is the heat created by the friction. Should I be worried about a cracked head and do you guys suggest I get the damn thing XRayed? Im a college student and money sure as hell wont grow on trees.

My other concern is wear matching. I know cams wear into their respective cam towers and caps. I will be buying a new cam and replacing the cam tower. Should I be concerned about the new cam wearing into a new, but used cam tower? And what about the tower I plan to keep that doesnt seem damaged.

Thanks everyone

[strynboen]

no problem,,, just bay used parts and build them in...its a old engine..all parts have some sluck..but a visual thek can be fine if you áre used to look on this type of engine parts,if not messuring all parts is a must...
and find aut vhy it have lost oilpresure...have there be used silicone fl gasket..vho blockes the restriktion valve to the head..or other failure..pump must be good if the other half engine are fine

[Lammers000]

Yes, it was gasket sealant that clogged the oil gallery.

[strynboen]

take the oil sump off. and filter and oil tank.and vash the engine/oill tank in fuel/gas..and blow pressured air through...so all small metal parts are vashed aut. take the oil pump aut too and vask and blow all oil lines through.then buildthe engine back up Again..is it a 750 the engine must aut..is it a 550 it can be in frame..personly, i just have baued used parts..and taken the chance the head are ok..and put it together and test ride it..thats just mine idea..let somone other give some ideas..

[seanbarney41]

I have had this exact problem happen but the oil blockage was caused by longterm storage rather than silicon.  The best thing to do is replace the whole valvetrain as a set, cam, towers and rockers, and shafts, all from the same engine.  This is what I did and most everything has been well for 9000 miles or so.  Good, used but mismatched parts can be used, it is just not as ideal.  The parts will have to re-establish a wear pattern and this will reduce the ultimate longevity of the parts but probably not to an unacceptable level.
    In my situation, cam and tower destruction was rapid and catastrophic and only on the #4 end of the engine, similar to yours.  I have no evidence of cylinder head damage as I have not yet torn the motor down beyond the cam towers.  However, my valve cover will no longer hold a seal for more than about 1000 miles, despite 3 new gaskets and attempts at "bodging it shut.  The leaks always begin on the #4 end of the engine.  I  believe the camshaft failure warped the valve cover or the gasket rail.

[HondaMan]

The damage that happens with a blocked journal is quick (like, 10 minutes max). It's exceedingly unlikely that the rest of the head got 'hurt' in the process.

[b5rider]

If there was blasting media left in the engine after a rebuild and it gouged the cam and head,  would I need to split the cases. The engine was only ran about 25 miles after the rebuild

[Lammers000]

If there were blasting media left in the engine period Id suggest a rebuild. Those particles can easily circulate throughout the whole bike and can wear out pieces here and there and cause uneven wear, thus decreasing the life of some parts. They can also do damage to your oil pump and other components in the bottom end so YES I do suggest splitting the case and cleaning everything thoroughly.

[b5rider]

If there were blasting media left in the engine period Id suggest a rebuild. Those particles can easily circulate throughout the whole bike and can wear out pieces here and there and cause uneven wear, thus decreasing the life of some parts. They can also do damage to your oil pump and other components in the bottom end so YES I do suggest splitting the case and cleaning everything thoroughly.

Thanks, I figured.